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Using the generic type 'System.Collections.Generic.List<T>' requires '1' type arguments

scspl
scspl asked
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Last Modified: 2013-12-17
I have used code to merge cells in gridview but it shows error


 Using the generic type 'System.Collections.Generic.List<T>' requires '1' type arguments


so can you help your suggest anything for the same???????
public static List<T> MakeList_tmp<T>(T temp)
        {
            List<T> newList = new List<T>();
            return newList;
        }
 
 
 
        private void mergeRows(GridView gv)
        {
            string lastColumn1 = string.Empty;
            
            GridViewRow currentRow = null;
            GridViewRow tmp = null;
            var temp = tmp;
            var tempRow = MakeList_tmp(temp);
            System.Collections.Generic.List tempRows = new System.Collections.Generic.List();
            
            foreach (GridViewRow row in gv.Rows)
            {
                if (row.RowType == DataControlRowType.DataRow)
                {
                    string currentColumn1 = string.Empty;
                    currentColumn1 = Convert.ToString(row.Cells[0].Text);
 
                    if (currentRow == null)
                    {
 
                        currentRow = row;
                        lastColumn1 = Convert.ToString(row.Cells[0].Text);
 
                    }
 
 
                    else
                    {
                        if (lastColumn1 != currentColumn1)
                        {
 
                            currentRow.Cells[0].RowSpan = tempRows.Count + 1;
                            currentRow.Cells[0].VerticalAlign = VerticalAlign.Middle;
                            currentRow.Cells[0].HorizontalAlign = HorizontalAlign.Center;
 
                            foreach (GridViewRow row1 in tempRows)
 
                                row1.Cells.RemoveAt(1);
                            lastColumn1 = currentColumn1;
 
                            tempRows.Clear();
                            currentRow = row;
                            lastColumn1 = currentColumn1;
                        }
                        else
                        {
 
                            tempRows.Add(row);
                        }
                    }
                }
            }
           
            if (tempRows.Count >= 0)
            {
                
                currentRow.Cells[0].RowSpan = tempRows.Count + 1;
                currentRow.Cells[0].VerticalAlign = VerticalAlign.Middle;
                currentRow.Cells[0].HorizontalAlign = HorizontalAlign.Center;
 
                foreach (GridViewRow row1 in tempRows)
                    row1.Cells.RemoveAt(0);
            }
        }
protected void GridView1_PreRender(object sender, EventArgs e)
        {
            GridView gv1 = (GridView)sender;
            mergeRows(gv1);
 
        }

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Billing Engineer
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Commented:
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Author

Commented:
So, if here

GridViewRow tmp = null;

List<GridViewRow> tempRows = MakeList_tmp();


i want to pass tmp with MakeList_tmp(tmp) so

how it should be written over here and how the argument will be passed to

the MakeList_temp() <----    function....
Guy Hengel [angelIII / a3]Billing Engineer
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Most Valuable Expert 2014
Top Expert 2009
Commented:
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Author

Commented:
it is not accepting that...

<T> tmp -->  is not a valid argument.....

so is there any other way...
public static List<T> MakeList_tmp<T>(<T> tmp)   
{
    List<T> newList = new List<T>();
    return newList;
}
 
 
 
 
// Above code generates the error:->
 
// Compiler Error Message: CS1031: Type expected

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Guy Hengel [angelIII / a3]Billing Engineer
CERTIFIED EXPERT
Most Valuable Expert 2014
Top Expert 2009

Commented:
sorry, in the method parameter data type, it's without the <>
public static List<T> MakeList_tmp<T>(T tmp)   
{
    List<T> newList = new List<T>();
    return newList;
}
 

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Author

Commented:
That matter is solved but tell me one thing

where will  the method  mergeRows() called?

will it be before databinding or after that???

Author

Commented:
now i got it it's working thanks a lot for your help


it will be called after binding the data to the data grid

other wise it will show the null reference error.

because it will not have any data into cells without binding..



thank you

again angel

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